Wow: list of immediate subclasses?

[Michael Hudson]

Michael Hudson <mwh at python.net> writes:

> "Andrew Dalke" <adalke at mindspring.com> writes:
> 
> > Carl Banks, responding to Roman Suzi:
> > > __subclasses__ is a list of weak references, so the class can be
> > > collected even though it's listed in __subclasses__.  For whatever
> > > reason, class A isn't deleted by reference counts, but cyclic garbage
> > > collection gets it.
> > 
> > But I want to know that reason.  Why are there any cycles?  
[...]
> 
> I don't know where the cycle is, off-hand.  I suspect I did once...

Found it (them):

>>> class A(object): pass
... 
>>> A.__dict__['__weakref__'].__objclass__ is A
True

praise-be-to-neils-ly y'rs
mwh

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